DISPLAY DEVICE RESISTANT TO IMPACT
20210135156 ยท 2021-05-06
Inventors
Cpc classification
B32B27/322
PERFORMING OPERATIONS; TRANSPORTING
B32B2307/746
PERFORMING OPERATIONS; TRANSPORTING
B32B5/16
PERFORMING OPERATIONS; TRANSPORTING
B32B9/043
PERFORMING OPERATIONS; TRANSPORTING
B32B2457/202
PERFORMING OPERATIONS; TRANSPORTING
B32B2307/42
PERFORMING OPERATIONS; TRANSPORTING
B32B25/042
PERFORMING OPERATIONS; TRANSPORTING
B32B9/007
PERFORMING OPERATIONS; TRANSPORTING
B32B5/18
PERFORMING OPERATIONS; TRANSPORTING
B32B7/12
PERFORMING OPERATIONS; TRANSPORTING
B32B5/30
PERFORMING OPERATIONS; TRANSPORTING
B32B9/04
PERFORMING OPERATIONS; TRANSPORTING
B32B19/04
PERFORMING OPERATIONS; TRANSPORTING
B32B5/32
PERFORMING OPERATIONS; TRANSPORTING
B32B19/043
PERFORMING OPERATIONS; TRANSPORTING
B32B2457/206
PERFORMING OPERATIONS; TRANSPORTING
B32B2307/546
PERFORMING OPERATIONS; TRANSPORTING
International classification
B32B27/06
PERFORMING OPERATIONS; TRANSPORTING
B32B27/28
PERFORMING OPERATIONS; TRANSPORTING
B32B5/18
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A light-emitting device includes a housing layer, a display located adjacent the housing layer and formed of a plurality of layers including a substrate layer, a window layer formed adjacent the display opposite the housing layer and bonded to the display, and an interface layer that is disposed between the substrate layer and the housing layer and enables a lateral distortion between the display and the housing layer. The interface layer may be configured such that a first resistance to shear between the display and the window is greater than a second resistance to shear between the substrate layer and the housing layer.
Claims
1. A light-emitting device comprising: a housing layer; a display located adjacent the housing layer and formed of a plurality of layers including a substrate layer; a window layer formed adjacent the display opposite the housing layer and bonded to the display; and an interface layer that is disposed between the substrate layer and the housing layer and enables a lateral distortion between the display and the housing layer.
2. The light-emitting device of claim 1, wherein a first resistance to shear between the display and the window is greater than a second resistance to shear between the substrate layer and the housing layer.
3. The light-emitting device of claim 1 or 2, wherein the interface layer is bonded to at least one of the substrate layer and the housing layer.
4. The light-emitting device of claim 3, wherein the interface layer is bonded to each of the substrate layer and the housing layer.
5. The light-emitting device of claim 4, wherein the interface layer is formed of a material having a low lateral stiffness.
6. The light-emitting device of claim 5, wherein the interface layer is formed of a foam material.
7. The light-emitting device of claim 1, wherein the interface layer is formed of a dry lubricant material or a solid lubricant material that is deposited on at least one of the display or the housing layer.
8. The light-emitting device of claim 7, wherein the interface layer is formed of a fluoropolymer material, a graphite material, or a molybdenum disulphide material.
9. The light-emitting device of claim 7, wherein the interface layer is formed of a particulate material.
10. The light-emitting device of claim 7, wherein the interface layer is formed of a material having a layered crystal structure.
11. The light-emitting device of claim 1, wherein the interface layer is formed of a viscous liquid material that adheres to at least one of the display or the housing layer.
12. The light-emitting device of claim 11, wherein the viscous liquid material is a mineral oil.
13. The light-emitting device of claim 11, wherein the interface layer includes a containment wall that contains the viscous liquid material.
14. The light-emitting device of claim 1, wherein the interface layer is formed of a pseudoplastic fluid material, a shear thinning fluid material, a pseudoplastic gel material, or a shear thinning gel material.
15. The light-emitting device of claim 1, wherein the interface layer is formed of a sheet of material that is unbonded relative to the display and the housing layer, and the interface layer is slideable along the housing layer.
16. The light-emitting device of claim 15, wherein the interface layer is formed of a fluoropolymer material.
17. The light-emitting device of claim 1, wherein the interface layer has a thickness that is between one and 300 microns.
18. The light-emitting device of claim 1, wherein the substrate layer is formed of a flexible material.
19. The light-emitting device of claim 1, wherein the substrate layer is formed of a polyimide material.
20. An electronic device comprising at least one light-emitting device according to claim 1, wherein the display includes at least one of a touch sensor layer, a polariser layer, and an adhesive layer.
Description
BRIEF DESCRIPTION OF DRAWINGS
[0017]
[0018]
[0019]
[0020]
[0021]
[0022]
[0023]
[0024]
[0025]
DESCRIPTION OF EMBODIMENTS
[0026] Embodiments of the present invention will now be described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. It will be understood that the figures are not necessarily to scale.
[0027] The present disclosure describes a light-emitting diode (LED) display device which includes a housing, a display formed of a plurality of layers including a substrate layer, a window layer that is bonded to the display, and an interface layer that is disposed between the display and the housing and enables a lateral distortion between the display and the housing. When an object collides with the window, the interface layer enables a lateral displacement of one or more layers of the display relative to the housing, and this may be effective in preventing the colliding object from causing permanent damage to one or more layers of the display. The lateral displacement of the display relative to the housing is enabled, for example, by providing an interface material in the interface layer which allows the interface layer to slide relative to the housing or the display. Accordingly, the display device has an improved resilience to damage caused by the impact of the object on the window, such as crack formation in one or more layers of the display.
[0028] The interface layer is formed of an interface material that is configured to provide a low resistance to shear occurring between a lower surface of the display and an upper surface of the housing. This resistance to shear is lower than a resistance to shear between an upper surface of the display and a lower surface of the window. As referenced throughout the present disclosure, the resistance to shear is defined as a displacement, such as a sliding movement, between two surfaces when subject to a force that causes a displacement between the surfaces. The present disclosure generally pertains to a force occurring in a direction that is normal or perpendicular to the plane of the surface or surfaces which are displaced, such that the displacement or movement occurs perpendicular relative to the direction of the force. The resistance to shear is inversely proportional to the displacement such that the resistance to shear is low when the displacement between the two surfaces is large for a given force, and the resistance to shear is high when the displacement between the two surfaces is low for the given force.
[0029] In an exemplary embodiment, the interface material of the interface layer may be bonded to at least one of the upper surface of the housing and the lower surface of the display. In other exemplary embodiments, the interface material may be bonded to both the housing and the display, and have a low stiffness in the lateral direction that enables a lateral displacement of the display and the layers fixed to the display relative to the housing.
[0030] In still other exemplary embodiments, the interface material may be unbonded relative to the display and the housing such that a lower surface of the interface material slides or slips over an upper surface of the housing in a lateral direction when subject to a force applied along a direction normal to the lateral direction.
[0031] In any configuration of the interface material within the display device as disclosed herein, when the display device is subject to a collision type of force in the normal direction relative to the plane of the display device or the lateral direction, a lateral distortion or displacement within the device layers will occur in the lateral direction to prevent permanent damage to one or more layers of the display. The lateral distortion may also be referred to as a lateral spreading.
[0032]
[0033] During a collision of an object against the window 106 of the conventional display device 100, a force F.sub.1 may be applied to the window 106 in a direction that is normal or perpendicular to the width w of the display device 100, such as in a positive z-direction, as shown in
[0034] Referring now to
[0035] In reference to directions, references to a bottom or lower element of the display device stack of any of the embodiments corresponds to a non-viewing side, and references to a top or upper element of the display device stack of any of the embodiments corresponds to a viewing side through which image light is emitted. Accordingly, the layers of display device 200, as representative, as ordered from the viewing side include the window 106, the display 104 with the substrate 116 being the non-viewing side layer of the display 104, the interface layer 112, and the housing 102. In addition, references to layers being adjacent to each other may exclude the adhesive layers (e.g., layer 110), as such adhesive layers generally perform a bonding function between two layers identified as adjacent.
[0036] The interface layer 112 extends in the x-direction or plane of the display device 200 and may extend along an entire width and/or length of the display device 200. In exemplary embodiments, the interface layer 112 may extend along a partial width and/or length of the display device 200. For example, the display device 200 may be flexible or bendable, such that the interface layer 112 is only arranged in areas of the display device 200 which are rigid and non-bendable. The interface layer 112 may have any suitable thickness. For example, the interface layer 112 may have a thickness that is between one and 300 microns. The thickness of the interface layer 112 may be similar to the thicknesses of other layers within the display 104 and less than the thickness of the housing 102 and the window 106.
[0037] The display 104 is formed of a plurality of layers including at least a substrate layer 116 on which any suitable pixel structure is formed. The substrate layer 116 is the layer of the display 104 that is nearest to the housing 102 and adjacent the interface layer 112. In an exemplary embodiment, the pixel structure formed on the substrate layer 116 may include an array of organic light-emitting diodes (OLEDs) which are operable as an active matrix display by way of circuits comprising thin film transistors (TFT) which are disposed on the substrate layer 116. The display device 200 may include any other suitable display that is disposed on the substrate layer 116. Examples of other suitable displays include quantum dot LED displays in which light emission is by electroluminescence from nanocrystal quantum dot materials disposed on the substrate layer 116. The substrate layer 116 may be formed of any suitable flexible material which enables the display device 200 to be bendable or flexible. Providing a flexible material may be particularly suitable for use in OLED displays, and an example of a suitable flexible material is a polyimide material. The substrate layer 116 may further comprise a shock absorbing element. A suitable shock absorbing element can be elastically (reversibly) deformed in the vertical direction (z-direction in
[0038] The plurality of layers of the display 104 may include any suitable number of layers that enhance the quality of the emitted image and display interface operations. In an exemplary embodiment of the display 104, the display 104 includes at least one of a touch sensor layer 118, an optical polariser layer 120, and multiple adhesive layers 122, 124 that are arranged between two adjacent layers for bonding. The touch sensor layer 118 may be a capacitive touch sensor formed from electrodes that are deposited on a polymer sheet, or any other suitable touch sensor. The optical polariser layer 120 may be a circular polariser, and the adhesive layers 122, 124 may have a low light absorption for light emitted from the display 104 and refractive indices that are similar to the layers which are being bonded by the adhesive layers 122, 124. For example, the adhesive layers 122, 124 may be formed of an indexed-matched optically clear adhesive. The layers of the display 104 are stacked in any suitable order or arrangement and in exemplary embodiments, the uppermost layer of the display 104 may be the optical polariser layer 120 and the bottommost layer of the display 104 may be the substrate layer 116.
[0039]
[0040] As shown in
[0041] In
[0042]
[0043] In the examples of
[0044] As shown in both
[0045] In one example, the lateral displacement facilitated by the interface layer 112 can enable a shock absorbing element within the display 104 to undergo larger vertical deformation for a given impact force in the vertical direction. When a force is applied to a shock absorbing element in a vertical direction (z-direction) the compressive strain in the vertical direction is lower if the shock absorbing element is constrained in the lateral direction than if it is not constrained. Therefore, if the lateral displacement of the lower surface of the display 104 is facilitated by the interface layer 112, a shock absorbing element in the display 104 may exhibit larger vertical displacement during the impact of an object 114. During impact of the object 114 on the window 106, the window 106 may elastically (reversibly) deform in the direction of motion of the object 114. The kinetic energy of the object 106 is partially converted into energy associated with the elastic deformation of the window 106. A larger compressive strain in the vertical direction in a shock absorbing element can therefore facilitate a larger elastic deformation of the window 106, absorbing a larger amount of energy associated with the elastic deformation of the window 106. Absorption of more energy of the impact in the window 106 may contribute to lower stress and strain in critical layers of the display 104 and therefore prevent damage to said critical layers. The interface layer 112 therefore enables a larger elastic deformation of a window 106 without requiring an increase in thickness of a shock absorbing element.
[0046]
[0047] In the simulation of
[0048] Referring now to
[0049] The interface layer 112 in the display device 400 may be formed of any suitable material. For example, a suitable material may be a dry lubricant or a solid lubricant material that is deposited onto at least one of the lower surface of the display 104 or the upper surface of the housing 102. Using a solid lubricant may be particularly advantageous in that solid lubricants may have a more consistent friction value over a wider range of operating temperatures of the display device 400. Additionally, a solid lubricant may be more easily applied and incorporated into the display device 400. Examples of suitable lubricant materials include a fluoropolymer material, graphite, and molybdenum disulphide. Polytetrafluoroethylene may be suitable. In exemplary embodiments, the interface material may be a particulate material or a material having a layered crystal structure.
[0050] In other exemplary embodiments, the interface material of the interface layer 112 may be in the form of any suitable liquid material, such as a viscous liquid material which adheres to at least one of the lower surface of the display 104 or the upper surface of the housing 102 and does not flow off of the surface during operating temperatures of the display device 300. A mineral oil material may be suitable. Using an oil material may be particularly advantageous in that the oil may have a consistently low resistance to shear over a wide range of operating temperatures of the display device 400. The resistance to shear may also remain low when the stress due to the collision with the window 106 is high.
[0051] In an exemplary embodiment in which the interface material is a liquid material, the interface layer 112 may further include a containment structure 126 for retaining the liquid material, such as a vertically-extending wall, barrier, or other suitable structure. The containment structure 126 may be used to prevent the liquid from being transported from outside of the interface layer 112. Using the liquid material may be further advantageous in that the liquid provides a barrier to the ingress of oxygen or water into the display device 400, such that the performance and lifetime of the display device 400 is enhanced.
[0052] In other exemplary embodiments, the interface material may be a gel, or another interface material that has shear thinning properties. Accordingly, the resistance to shear may be reduced as the change in the shear strain, or shear strain rate is increased, such as during the collision on the window 106 of the display device 300. Examples of suitable materials include a pseudoplastic fluid material, a shear thinning fluid material, a pseudoplastic gel material, or a shear thinning gel material. In this case, the interface layer 112 may advantageously provide low resistance to shear during an impact but higher resistance to shear at other times. Referring to the example described above that the low resistance to shear in the interface layer 112 may facilitate a large vertical deflection of a shock absorbing element in the display 104 during an impact, if the interface material of the interface layer 112 has shear thinning properties, the vertical deflection of the shock absorbing element may be lower during routine operation of the display devicefor example providing a low vertical deflection when a user touches the window 106 during conventional operation of the touch sensor of a display and the strain rate is lowbut provide advantageously large vertical compression during an impact where the strain rate is high.
[0053] As shown in
[0054] As shown in
[0055] An aspect of the invention is a light-emitting device including a housing layer, a display located adjacent the housing layer and formed of a plurality of layers including a substrate layer, a window layer formed adjacent the display opposite the housing layer and bonded to the display, and an interface layer that is disposed between the substrate layer and the housing layer and enables a lateral distortion between the display and the housing layer.
[0056] In an exemplary embodiment of the light-emitting device, a first resistance to shear between the display and the window is greater than a second resistance to shear between the substrate layer and the housing layer.
[0057] In an exemplary embodiment of the light-emitting device, the interface layer is bonded to at least one of the substrate layer and the housing layer.
[0058] In an exemplary embodiment of the light-emitting device, the interface layer is bonded to each of the substrate layer and the housing layer.
[0059] In an exemplary embodiment of the light-emitting device, the interface layer is formed of a material having a low lateral stiffness.
[0060] In an exemplary embodiment of the light-emitting device, the interface layer is formed of a foam material.
[0061] In an exemplary embodiment of the light-emitting device, the interface layer is formed of a dry lubricant material or a solid lubricant material that is deposited on at least one of the display or the housing layer.
[0062] In an exemplary embodiment of the light-emitting device, the interface layer is formed of a fluoropolymer material, a graphite material, or a molybdenum disulphide material.
[0063] In an exemplary embodiment of the light-emitting device, the interface layer is formed of a particulate material.
[0064] In an exemplary embodiment of the light-emitting device, the interface layer is formed of a material having a layered crystal structure.
[0065] In an exemplary embodiment of the light-emitting device, the interface layer is formed of a viscous liquid material that adheres to at least one of the display or the housing layer.
[0066] In an exemplary embodiment of the light-emitting device, the viscous liquid material is a mineral oil.
[0067] In an exemplary embodiment of the light-emitting device, the interface layer includes a containment wall that contains the viscous liquid material.
[0068] In an exemplary embodiment of the light-emitting device, the interface layer is formed of a pseudoplastic fluid material, a shear thinning fluid material, a pseudoplastic gel material, or a shear thinning gel material.
[0069] In an exemplary embodiment of the light-emitting device, the interface layer is formed of a sheet of material that is unbonded relative to the display and the housing layer, and the interface layer is slideable along the housing layer.
[0070] In an exemplary embodiment of the light-emitting device, the interface layer is formed of a fluoropolymer material.
[0071] In an exemplary embodiment of the light-emitting device, the interface layer has a thickness that is between one and 300 microns.
[0072] In an exemplary embodiment of the light-emitting device, the substrate layer is formed of a flexible material.
[0073] In an exemplary embodiment of the light-emitting device, the substrate layer is formed of a polyimide material.
[0074] In an exemplary embodiment of the light-emitting device, an electronic device includes at least one light-emitting device in which the display includes at least one of a touch sensor layer, a polariser layer, and an adhesive layer.
[0075] Although the invention has been shown and described with respect to a certain embodiment or embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described elements (components, assemblies, devices, compositions, etc.), the terms (including a reference to a means) used to describe such elements are intended to correspond, unless otherwise indicated, to any element which performs the specified function of the described element (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one or more of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.
INDUSTRIAL APPLICABILITY
[0076] The present invention relates to LED devices that, for example, may be used for light-emitting elements in a display device. Embodiments of the present invention are applicable to many display devices to permit display devices of high resolution and high image quality. Examples of such devices include televisions, mobile phones, personal digital assistants (PDAs), tablet and laptop computers, desktop monitors, digital cameras, and like devices for which a high resolution display is desirable.
REFERENCE SIGNS LIST
[0077] 100conventional display device [0078] 102housing [0079] 104display [0080] 106window [0081] 108adhesive layer [0082] 110adhesive layer [0083] 112interface layer [0084] 114object that impacts display [0085] 116substrate layer [0086] 118touch sensor layer [0087] 120optical polariser layer [0088] 122adhesive layer [0089] 124adhesive layer [0090] 126containment structure [0091] 128first interface material [0092] 130second interface material [0093] 200display device [0094] 300display device [0095] 350display device [0096] 400display device [0097] 500display device